


What Might Soothe You?

by Butterfly_Dream



Category: Love Live! Sunshine!!
Genre: Aged-Up Character(s), Creampie, F/F, Futanari, I'm not sorry, Incest, Large Cock, Shameless Smut, Sibling Incest, ruby's got a big dick, slight size kink
Language: English
Status: Completed
Published: 2019-11-01
Updated: 2019-11-01
Packaged: 2021-01-18 06:09:42
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,783
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21270770
Author URL: https://archiveofourown.org/users/Butterfly_Dream/pseuds/Butterfly_Dream
Summary: A routine weekend spent apart leaves Dia yearning for the warmth of Ruby's presence once more.
Relationships: Kurosawa Dia/Kurosawa Ruby
Comments: 9
Kudos: 49





	What Might Soothe You?

**Author's Note:**

> dw they're both adults here everyone nothing to see here just move on  
thanks to [mecchacumming](https://archiveofourown.org/users/mecchacumming) for cleaning this up a bit. not like any amount of cleaning will absolve me of this sin. just some good old-fashioned family love :)

An airy sigh passed the corners of Dia’s lips. She lay perfectly still, staring up at the ceiling, but she was awake and alert as ever. In an effort to gain some sort of control back from her restless mind, she sorted through the day’s events in her head.

Class was uneventful. So was the bus ride home, and the weekly grocery shopping for her and Ruby. Then she’d gone straight to her room and stuck her nose in her studies, but found herself drowning in the political jargon and dull history. Such subjects usually kept her interest, but today she could pin the start of her ongoing restlessness to that very moment.

Or perhaps it was her trip to the grocery store. A cashier even had the wherewithal to point out Dia’s good mood during checkout, upon which Dia quickly wiped the smile from her face. Once she got home and the hours dragged on, her excitement gave way to anxiety over Ruby's return to their Tokyo apartment. As she did every week, Dia had spent the weekend alone while Ruby returned home. Dia would have preferred otherwise, but that wasn’t her decision to make.

The very idea of Ruby leaving home to attend college had been nothing short of ludicrous to their parents. After many exhausting dinnertime conversations, voices being raised, and family members being brought to tears, they finally relented, though not without a comprehensive list of conditions, which included daily check-ins and visits home to Uchiura on the weekends. Though still very much under the watchful eye of their parents, Ruby treasured her newfound freedom. So did Dia.

Dia preferred not to go home on the weekends, however. The questions lobbied her way tended to stray towards undesirable topics. If she had a hundred yen for how many times her parents had used the words “suitor,” “partner,” or “family tradition” in the three years she’d been away, she could put a down payment on her very own house. The very thought of tying herself down in marriage made her skin crawl and her heart overturn in a bout of anxiety. She hurriedly sat up, massaging her temples. She had laid down earlier to try and steady her nerves, but she’d only succeeded in working herself up even further. She swung herself out of bed. When was Ruby coming home? Did she run into a delay?

Dia shook her head to clear herself of the steady incline of anxious thoughts. She still had groceries sitting in the fridge that she needed to make good use of.

About an hour later, as Dia’s head rested in her hands at the kitchen table, the doorbell rang. The chair clattered behind her as she stood up, sending a new rush of emotions to her head. She made her way to the door, taking care to compose herself along the way.

But when she opened the door and her sister was there to meet her, weary from a long day of traveling yet smiling all the same, Dia couldn’t contain herself any longer. She pulled Ruby in and wrapped her in a fierce hug. A surprised noise akin to a squeak escaped Ruby, but she quickly reciprocated the embrace. Warmth bloomed through Dia, and she let herself bask in the moment, for fear of the moment she’d have to let Ruby go again.

Their weekly routine had become just that: routine. Normal. But no matter how much Dia assured herself that she could last two whole days alone in the apartment, the desperate loneliness simply clawed its way back into her heart before long. She knew she couldn’t take it out on her parents, or worse still, Ruby herself. No one was to blame for the deafening silence in the apartment when her little sister left for the weekend. No one was to blame for the chewed nails at the end of Dia’s fingertips every Sunday night. Dia couldn’t bear to confess the loneliness she felt to Ruby. Dia had the responsibility to look after her little sister, not the other way around - she couldn’t stand to feel like a burden. So whenever the doorbell rang on Sunday night and Ruby stood on the other side of the door once again, their reunion was almost worth it. Almost.

Dia felt Ruby squirm restlessly in her arms, and immediately she loosened her grip. Holding her sister at arm’s length, they shared a knowing look full of love. Dia basked in the sight; Ruby’s shy demeanor, while less pronounced than her high school days, was still apparent, especially to those who knew her well. It was on full display as Ruby rocked back and forth on her heels, unable to stand still. Dia was filled with a compulsion to protect her younger sister, and that was something she thought would never change.

For now, she took Ruby’s hand and guided her to the kitchen, where she’d prepared a simple meal for the two of them: sweet potato soup, Ruby’s favorite. Predictably, Ruby’s eyes lit up, and her obvious joy was contagious. Little moments like this, where Dia could see and treasure her little sister’s joy all to herself, were what kept her going.

Dinner was slow and conversation was minimal, but Dia didn’t mind. After exhausting the usual topics of their parents and school, a comfortable silence blanketed the both of them. Ruby cast her eyes downward, her eyes glued to her bowl. Dia found her own eyes drifting back to Ruby of her own accord. In the years since their time in Aqours, Ruby hadn’t grown much. She’d left her cutesy twintails behind in favor of wearing her hair down, or tying it up in a bun, and some of her face had lost that childlike cuteness that defined her first year of high school. She looked more mature, or maybe less immature. Her petite figure, large eyes, and high-pitched voice remained as her defining, cute characteristics.

Ruby looked up to see Dia staring at her. She nodded quickly and whipped her head away, blushing. Dia was confident they had the same thing on their minds, but for now, she sat back and let herself enjoy her sister’s presence.

Dinner was soon over, and they took their time washing the dishes, splitting the duties evenly between each other. When the last utensil was put away, Ruby’s hand fell naturally into Dia’s, and they proceeded to their shared bedroom.

The moment they stepped foot across the private threshold of their bedroom, Ruby allowed herself to be swept up into Dia’s passionate embrace. When their lips met, the warmth of their bodies spread to their lips, filling a singular vacuum occupied only by the two of them.

Their love had to be kept secret from the world, but that meant their clandestine couplings were all the more heated, all the more passionate. Neither of them said a word. Dia’s light caresses, their mingled breaths, Ruby’s restrained gasps for air, communicated everything they both needed to know. So did her hands, which roamed Dia’s back and shoulders. Dia, meanwhile, caressed Ruby’s face with loving hands, deepening the kiss with her tongue, which Ruby gladly accepted.

Ruby’s hands moved lower, tugging at the waistband of Dia’s black plaid pants. Dia shifted her hips, and after a few more tries, the pants fell to her ankles. She quickly shook them off and they fluttered to the floor, forgotten. Next to go was her fluttery white blouse, which she yanked off herself in her haste. It too met the same fate.

Ruby stepped back, drinking in the sight of her sister’s body. Flushed, Dia watched Ruby examine her, breathing heavily. Though she hadn’t worn any particularly titillating undergarments today, she didn’t need to. Their mere proximity to each other was more than enough. Then, without a word, Ruby leaned back into her embrace, kissing her with passion.

Ruby’s clothes were next to go. She wore a simple blue knee-length dress, but not for much longer. Hers was simpler to undress; Dia simply had to undo the back zipper and off it fell from her slim figure. Like Dia, Ruby’s choice of underwear was plain, but Dia didn’t mind. Besides, she had more pressing matters to attend to; particularly, the strained tent in Ruby’s crotch, yearning to break free of the fabric. Dia facilitated this endeavor without a word, her experienced fingers diving beneath Ruby’s panties and stroking the half-erect member underneath. Ruby gasped, quivering with silent pleasure as Dia worked her hand up and down her length. Her underwear couldn’t contain the length of her dick for much longer.

When Ruby couldn’t handle the discomfort anymore, Dia pulled down her panties, letting her cock finally swing free. It was true that Ruby still possessed many cute features. Her imposing nine-inch cock was not one of those features, and right now it contrasted greatly with her modest breasts. The same was true for her balls, neither of which could be contained by the paper-thin lingerie that others would have preferred for this type of foreplay. Though such a length would have been terrifying to most, the sight of it after days of them being apart caused Dia to bite down on her lip so that any premature gasps of bliss wouldn’t escape her. It was her duty as Ruby’s older sister to relieve her, since she was sure no one else could properly take something of that length.

Dia couldn’t wait a moment longer. Her legs shaky with excitement, she led Ruby to the edge of the bed, wasting no time in crawling onto the sheets stomach-down, raising her rear and pulling her damp panties down to her knees. Ruby followed suit, kneeling behind her so the head of her thick cock rubbed against Dia’s lower lips. Their sighs mingled in the air, the head of Ruby’s impressive length soon soaked in her sister’s carnal juices.

Dia used her fingers to spread her newly-shaven, glistening pussy. She looked over her shoulder and beheld her sister for a long moment, nervous and still poised to make love to her. The head of her impressive cock pressed against her entrance, and still Ruby hesitated.

“Take me, Ruby.”

It was more of a request than a demand. Dia would never force Ruby beyond her comfort zone, but she knew Ruby wanted this as much as she did. She only had to be gentle, yet firm, and she knew that their shared desires would be linked in this moment.

Ruby gave her sister the tiniest of nods, placing her usually dainty hands firmly on Dia’s hips. She inched her own hips forward, and at long last, her cock parted Dia’s lower lips. In unison, a desperate sigh passed both of their lips. Their long-awaited union never failed to send Dia into a dizzying glee. Perhaps next time, she could go home with Ruby and their couplings could take place in the privacy of her old room. The idea sent a shiver of pleasure down her spine, one which only increased as Ruby made slow, deliberate headway, her cock spreading apart inch after inch of Dia’s pussy.

Ruby knew all the little intricacies of their love-making. She knew to start slow, that they both wanted to savor this initial coupling after days of being apart. Her weekend trips made her yearn for Dia’s comforting presence, replacing what should have been an uneventful sabbatical with an irreplaceable loneliness in the pit of her stomach. Their clandestine couplings, frequent and passionate, made up for this empty feeling, but only when they could be joined like this.

Finally, after what seemed like hours, Ruby bottomed out. Dia gave her another look over her shoulder, the burning passion of her gaze telling Ruby only one thing. Their eyes stayed locked as Ruby pulled out, delaying for one agonizing moment before thrusting forward once more, her entire length sinking into Dia’s welcoming pussy.

Dia mashed her face into the pillow, failing to stifle her shameless moans. Each and every one of Ruby’s thrusts into her filled her with all nine inches of dick. Gradually, Ruby sped up until her hips slapped against Dia’s ass each time she hilted herself, quickly joining their combined moans as the prevalent sound in the room.

Their deliberate love-making devolved into full-on fucking. Ruby’s eyes greedily sucked up every detail of her sister’s body. Dia usually looked so mature. Her straight black hair was now in disarray, and her curves, while not exaggerated by any means, seemed all the more alluring as she quivered with pleasure. And she was beneath Ruby, completely surrendering herself to her. Her pussy stretched around Ruby’s extensive length. She was Ruby’s and Ruby’s alone. Ruby never wanted this to end, but she already felt an orgasm building in the base of her dick.

Dia was being railed by her little sister. Ruby, usually so cute and demure, was above her, calling for her older sister in the throes of pleasure. The full realization of what they were doing rocked Dia’s body in orgasm, her inner juices making Ruby’s cock slick with their love as she pistoned in and out.

Dia also knew precisely how long Ruby could last. Starting slowly like they did also helped Ruby hold out for longer, but her limit was at about five minutes. That time was approaching fast. Her forehead already glistening with sweat, feeling another orgasm building in her core, Dia wanted them to cum together. She rocked her hips back every time she took in Ruby’s length, feeling it twitch needily against her walls. She looked over her shoulder once more. She wanted to see Ruby when she came. Her eager thrusts, aiding Ruby’s, told Ruby one thing: _Cum inside me._

Ruby, of course, was more than happy to listen. Her voice broke sharply. The floodgates of her climax opened, and she gave one final, powerful thrust to lock herself inside Dia. Her cock spurted, finally delivering ropes of warm, thick seed inside her sister. The overbearing pleasure of her climax, combined with Dia’s pussy pulsating around her cock, caused the spasms to spread through her whole body, digging her fingers into Dia’s hips and curling her toes in pure delight. Her mind was swarmed with this overload, and her moans gushed out her mouth, throwing her head back as she emptied herself inside.

Dia felt the warmth of Ruby’s cum pooling in her womb, and the feeling rocked her body, her limbs twitching uncontrollably as she shook with orgasm. Her pussy squeezed and contracted around Ruby’s length, aiding her sister’s climax as she continued to cum inside. The whole time, Dia’s eyes never left Ruby’s body, engrossed in the way her head was tilted back, and her cute open mouth which spilled moans and calls for Dia alike. Never had she felt so content, so complete, as when they were joined like this, sharing the apex of pleasure with each other. As sisters and as lovers, their connection was more total, more unconditional than any other.

In much the same way they shared their climax, they came down together as well. They relaxed, a few stray spasms lingering through Dia’s body, feeling the warmth of Ruby’s love inside of her. Ruby was spent and she pulled out slowly, a modest trickle of cum dripping out of Dia.

With nothing to hold her up, Dia was exhausted, and she rolled over slowly to rest on her back. Sweat dotted the circle of the pillow that encompassed her head, and she grimaced, feeling her own spittle as an after-effect from her climax. She held her arms out to Ruby, who crawled forward to nestle herself in her older sister’s embrace. She wrestled with the straps of Dia’s bra, which she hadn’t yet discarded even throughout their coupling, and Dia shifted to let it fall off of her. Ruby kissed her breasts lovingly, and Dia ran her hands through Ruby’s bright red hair, holding her close. The heat from Ruby’s spent cock pressing against her stomach. No words needed to be exchanged, lest they ruin the ephemeral halo of their afterglow. Together, sore from extended climax and sweaty from exertion, they knew they had each other’s back, no matter what.

Dia planted a kiss on the top of Ruby’s head, and Ruby sighed contentedly, pressing their bodies together even closer. Dia closed her eyes, basking in the warmth of Ruby’s seed inside of her. She knew she’d have to get up sooner rather than later, but the perfection of their lovemaking was something she’d carry with her always.

“I love you, Ruby.”

“I love you too, Onee-chan.”

**Author's Note:**

> only god can judge me


End file.
